* Split out decompress code from `download_and_verify`
* Clean the code to recieve keys
* Split out `aria2_options` array
* Tweak `aria2_options`
* `download_and_verify` always require `asc` file
* Download torrent from multi origin
* Refactor `get_urls` which renamed from `webseed`
* Add Github source to download rootfs cache
* Remove some useless check
* Change the argument of `download_and_verify`
* We don't need `complete` file
* Delete files when verification failed
* Adapt the refactored `download_and_verify`
* Remove useless config `ARMBIAN_MIRROR`
* Bugfix: verify never fail
* Specify directory argument instand of cd
8b2b14de40